Get the Last JSON-RPC Response from an MCP Server

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Demonstrates Mcp.GetLastJsonData, which returns the complete JSON-RPC response envelope (the jsonrpc, id, and result members) from the most recent request into a JsonObject.

Tip: Code to parse the returned JSON can be generated with Chilkat's online tool at https://tools.chilkat.io/jsonParse.

const std = @import("std");
const chilkat = @import("chilkat");

pub fn main(init: std.process.Init) !void {
    const alloc = init.arena.allocator();

    const mcp = try chilkat.Mcp.init();
    defer mcp.deinit();

    // Connect to a public MCP (Model Context Protocol) server over its Streamable HTTP endpoint.  The
    // Microsoft Learn MCP server is public and requires no authentication.
    mcp.connect("https://learn.microsoft.com/api/mcp") catch {
        std.debug.print("{s}\n", .{try mcp.getLastErrorText(alloc)});
        return;
    };

    // Perform an MCP request.
    const tools_result = try chilkat.JsonObject.init();
    defer tools_result.deinit();
    mcp.listTools(tools_result) catch {
        std.debug.print("{s}\n", .{try mcp.getLastErrorText(alloc)});
        return;
    };

    // Get the complete JSON-RPC response envelope (the jsonrpc, id, and result members) from the most
    // recent request.
    const json = try chilkat.JsonObject.init();
    defer json.deinit();
    mcp.getLastJsonData(json);

    json.setEmitCompact(false);
    std.debug.print("{s}\n", .{try json.emit(alloc)});
    // JSON parsing code for this result can be generated at Chilkat's online tool:
    // https://tools.chilkat.io/jsonParse
}